Percy CL, Smith MA, Linet M, et al. Cancer Incidence and Survival among Children and Adolescents: United States SEER Program 1975-1995: Lymphomas and Reticuloendothelial Neoplasms [Surveillance, Epidemiology, and End Results Web site]. November 5, 1999. National Cancer Institute: Surveillance Epidemiology and End Results. Available at http://www.seer.cancer.gov.